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Is Fluoride Dangerous?


Some alarming articles have appeared in the media recently about the safety of public water fluoridation. Consequently many parents have genuine concerns about potential effects on their children’s health. The addition of fluoride to public water supplies has been shown to cause a significant reduction in levels of dental decay. Whilst water fluoridation is an effective tool in the prevention of dental decay, there are a number of alternative methods of delivering fluoride. Water fluoridation involves ingestion of fluoride. The use of fluoride toothpaste, mouth rinses and professionally applied fluoride varnishes and gels do not involve fluoride ingestion and have also been proven to be very effective at reducing dental disease in children. There are certain risks involved when exposing small children to fluoride products which all parents should be aware of.

Parents have genuine concerns regarding the safety of fluoride. According to the most recent World Health Organisation data, 0.8-1.2mg per litre of fluoride in water has been associated with a sharp fall in tooth decay. There is an added benefit of bone strengthening at this concentration. Levels of fluoride above 1.5mg per litre are associated with a condition called dental fluorosis. This condition can cause mottling and or pitting of surface of affected teeth. Most dental fluorosis however, is unnoticeable to the untrained eye and is preferable to tooth decay. Exposure to fluoride levels of 10mg per litre of water can cause a crippling bone disease called skeletal fluorosis.

Fluoride has a unique mechanism of action. For many years it was supposed that fluoride had to be ingested and taken into the body to be effective. This was the thinking behind taking fluoride tablets and supplements to prevent decay. In the late nineties researchers showed that this was not the case. We now know that fluoride only needs to come in contact with the surface of a tooth to prevent decay. Fluoride exchanges with calcium and phosphate in the tooth’s structure making the tooth harder. The harder the tooth the less likely it is to develop decay.

Fluoride is a naturally occurring mineral which can be found in fish, tea and in many vegetables and crops. It can be found naturally in water in different parts of the world. It is contained in different levels in toothpastes and mouth rinses. High concentration fluoride varnishes are available for professional use.

The ethics of water fluoridation have been argued since the mandatory introduction of fluoride to public water supplies in this country. In the longest running court case in the history of the Irish state, Gladys Ryan vs Attorney General claimed in the Supreme Court that water fluoridation violated the Constitution of Ireland’s guarantee of the right to bodily integrity. The case was lost in favour of water fluoridation on the grounds that fluoridation was found to be safe at the levels recommended for use in public water. Tooth decay was a major public health concern and fluoride had been proven to be very effective at reducing the burden of dental disease in the population.

Since that court case tooth decay is still a burden on the health of the population; dental decay is still the most common chronic disease of childhood. Currently there is no evidence to show any more serious effects from public water fluoridation at current levels in Ireland’s water, than dental fluorosis. There are some facts that have changed since then. The first is our understanding of how fluoride works. Once we thought fluoride had to be ingested, whereas now we know this is not the case. The use of bottled water is more common now than it was in the 1960s and that makes it more difficult to see the impact of public water fluoridation. Toothpastes containing fluoride only became available in Ireland after the 1960s.

The most likely source of fluoride poisoning in a country such as Ireland is when a small child eats the contents of a tube of toothpaste. Thankfully reported deaths are rare however, fluoride poisoning in young children is a serious medical emergency and that is why small children should always be supervised when using fluoride products. Toothpaste should be kept out of the reach of little hands.

Children are a very vulnerable group in society. Tooth decay is caused in the main by diet and has a lot in common with heart disease and type II diabetes and obesity. They are all chronic diet related diseases. Sadly, all of these diseases are found more often in the lower socioeconomic groups. The “catch 22” is that those with the worst tooth decay are the least likely to be able to afford dental care. Water fluoridation was introduced as a cost effective way of protecting the less well off in the community. Water fluoridation could therefore, be seen as a way of reducing inequalities in health.

Parents should ensure that they receive advice from an appropriately trained dental professional before administering any fluoride products to young children- yet another reason why the first dental visit should coincide with the eruption of the first tooth!

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